Ecoregions of North Carolina

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Ecoregions of North Carolina and South Carolina (EPA)

July 6, 2008, 9:48 pm
300px-Ecoregions of North Carolina and South Carolina.JPG Ecoregions of North Carolina and South Carolina.

Ecoregions denote areas of general similarity in ecosystems and in the type, quality, and quantity of environmental resources. They are designed to serve as a spatial framework for the research, assessment, management, and monitoring (Environmental monitoring and assessment) of ecosystems and ecosystem components. By recognizing the spatial differences in the capacities and potentials of ecosystems, ecoregions stratify the environment by its probable response to disturbance (Bryce and others, 1999). These general purpose regions are critical for structuring and implementing ecosystem management strategies across federal agencies, state agencies, and nongovernment organizations that are responsible for different types of resources within the same geographical areas (Omernik and others, 2000).

The approach used to compile this map is based on the premise that ecological regions are hierarchical and can be identified through the analysis of the spatial patterns and the composition of biotic and abiotic phenomena that affect or reflect differences in ecosystem quality and integrity (Wiken 1986; Omernik 1987, 1995). These phenomena include geology, physiography, vegetation (Land-cover), climate, soils, land use, wildlife, and hydrology. The relative importance of each characteristic varies from one ecological region to another regardless of the hierarchical level. A Roman numeral hierarchical scheme has been adopted for different levels of ecological regions. Level I (Ecoregions of North Carolina and South Carolina (EPA)) is the coarsest level, dividing North America into 15 ecological regions. Level II (Ecoregions of North Carolina and South Carolina (EPA)) divides the continent into 52 regions (Commission for Environmental Cooperation Working Group 1997). At Level III (Ecoregions of North Carolina and South Carolina (EPA)), the continental United States contains 104 ecoregions and the conterminous United States has 84 ecoregions (United States Environmental Protection Agency [USEPA] 2002). Level IV (Ecoregions of North Carolina and South Carolina (EPA)) is a further subdivision of level III ecoregions. Explanations of the methods used to define the USEPA’s ecoregions are given in Omernik (1995), Omernik and others (2000), and Gallant and others (1989).

Ecological and biological diversity of the Carolinas is enormous. The two states contain barrier islands and coastal lowlands, large river floodplain forests, rolling plains and plateaus, forested mountains, and a variety of aquatic habitats. There are 5 level III ecoregions and 29 level IV ecoregions in North Carolina and South Carolina and most continue into ecologically similar parts of adjacent states.

350px-Level III Ecoregions of the Conterminous United States.jpg Level III Ecoregions of the Conterminous United States. (Map source: USEPA, 2000)

The level III and IV ecoregions on this poster were compiled at a scale of 1:250,000 and depict revisions and subdivisions of earlier level III ecoregions that were originally compiled at a smaller scale (USEPA 2002; Omernik 1987). This poster is part of a collaborative project primarily between USEPA Region IV, USEPA National Health and Environmental Effects Research Laboratory (Corvallis, Oregon), North Carolina Department of Environment and Natural Resources (NCDENR), South Carolina Department of Health and Environmental Control (SCDHEC), and the United States Department of Agriculture-Natural Resources Conservation Service (NRCS). Collaboration and consultation also occurred with the United States Department of Agriculture-Forest Service (USFS), United States Department of the Interior-Geological Survey (USGS)-Earth Resources Observation Systems (EROS) Data Center, and with other State of North Carolina and State of South Carolina agencies.

The project is associated with an interagency effort to develop a common framework of ecological regions (McMahon and others, 2001). Reaching that objective requires recognition of the differences in the conceptual approaches and mapping methodologies applied to develop the most common ecoregion-type frameworks, including those developed by the USFS (Bailey and others, 1994), the USEPA (Omernik 1987, 1995), and the NRCS (U.S. Department of Agriculture-Soil Conservation Service, 1981). As each of these frameworks is further refined, their differences are becoming less discernible. Regional collaborative projects such as these in North Carolina and South Carolina, where some agreement has been reached among multiple resource management agencies, are a step toward attaining consensus and consistency in ecoregion frameworks for the entire nation.

45. Piedmont
Considered the non-mountainous portion of the old Appalachians Highland by physiographers, the northeast-southwest trending Piedmont ecoregion comprises a transitional area between the mostly mountainous ecoregions of the Appalachians to the northwest and the relatively flat coastal plain to the southeast. It is a complex mosaic of Precambrian and Paleozoic metamorphic and igneous rocks with moderately dissected irregular plains and some hills. Once largely cultivated, much of this region is in planted pine or has reverted to successional pine and hardwood woodlands. The historic oak-hickory-pine forest was dominated by white oak (Quercus alba), southern red oak (Quercus falcata), post oak (Quercus stellata), and hickory (Carya spp.), with shortleaf pine (Pinus echinata), loblolly pine (Pinus taeda), and to the north and west, Virginia pine (Pinus virginiana). The soils tend to be finer-textured than in coastal plain regions.

45a. The Southern Inner Piedmont is generally higher in elevation with more relief than 45b. As a transitional region from the Blue Ridge (66) to the Piedmont, it contains some mountain outliers, and it receives more rainfall than 45b and 45c. The rolling to hilly well-dissected upland contains mostly gneiss and schist bedrock that is covered with clayey and micaceous saprolite. It is warmer than 45e to the north, and contains thermic soils rather than 45e’s mesic soils. The region is now mostly forested, with major forest types of oak-pine and oak-hickory, and less loblolly-shortleaf pine forest than 45b. Open areas are mostly in pasture, although there are some small areas of cropland.

45b. The Southern Outer Piedmont ecoregion has lower elevations, less relief, and less precipitation than 45a. The landform class is mostly irregular plains rather than the plains with hills of 45a and 45e. Pine (mostly loblolly and shortleaf) dominates on old field sites and pine plantations, while mixed oak forest is found in less heavily altered areas. Gneiss, schist, and granite are typical rock types, covered with deep saprolite and mostly red, clayey subsoils. Kanhapludults are common soils, such as the Cecil, Appling, and Madison series. Some areas within this region have more alkaline soils, such as the Iredell series, formed over diabase, diorite, or gabbro, and may be associated with areas once known as blackjack oak prairies.

45c. The Carolina Slate Belt extends from southern Virginia, across the Carolinas, and into Georgia. The mineral-rich metavolcanic and metasedimentary rocks with slatey cleavage are finer-grained and less metamorphosed than most Piedmont regions. Some parts are rugged, such as the Uwharrie Mountains, and many areas are distinguished by trellised drainage patterns. Silty and silty clay soils, such as the Georgeville and Herndon series, are typical. Streams tend to dry up and water yields to wells are low as this region contains some of the lowest water-yielding rock units in the Carolinas.

45e. Similar to 45a, the rolling to hilly Northern Inner Piedmont has higher elevations, more rugged topography, and more monadnocks or mountain outliers than other areas of the Piedmont. It has colder temperatures, more snowfall, and a shorter growing season than in 45a, b, c, and f, and it has mostly mesic soils rather than the thermic soils that cover other regions of the Carolina Piedmont. The region contains more Virginia pine and less shortleaf pine than 45b and 45c, more chestnut oak, and many mountain disjunct plant species. Streams tend to have higher gradients than in the Outer Piedmont regions, and contain many mountain-type macroinvertebrate species.

45f. The Northern Outer Piedmont is composed of mostly gneiss and schist rock intruded by granitic plutons, and veneered with saprolite. It is lithologically distinct from the adjacent Piedmont regions 45c and 45g, as well as from the younger unconsolidated sediments of 65m. Rocks and soils are similar to 45b, but 45f is cooler with a shorter growing season. The region contains more loblolly pine compared to the Virginia pine and shortleaf pine found in the Piedmont to the west, but it also contains local concentrations of mountain disjunct plant species. At the eastern boundary, the Fall Line is a broad transition zone where Piedmont rocks occur on the same landscape with Coastal Plain sediments. Some areas near this boundary have metavolcanic and metasedimentary rocks similar to 45c.

45g. The Triassic Basins of the Carolinas occur in four narrow bands and have unusual Piedmont geology of unmetamorphosed shales, sandstones, mudstones, siltstones, and conglomerates. Local relief and elevations are often less than in surrounding regions, and, with rocks that are easier to erode, stream valleys that cross the region tend to widen. Soils tend to be clayey with low permeability, and streams have low base flows. The clay has a high shrink-swell potential that can hinder construction; it is also utilized by many brick makers in the region. A mosaic of mixed and deciduous forest, pasture, cropland, and urban land cover occurs here.

45i. The Kings Mountain ecoregion is a hilly, somewhat rugged area with some northeast- to southwest-trending ridges and distinctive metasedimentary and metavolcanic rocks. Aluminum-rich quartz-sericite schist is common. The metamorphic grade is generally lower than adjacent geologic belts and the rocks contain an unusual variety of mineral deposits. Mining strongly influenced the early development of the region, including an iron industry in the late 1700’s to late 1800’s, and later production of marble, lime, gold, lead, silver, pyrite, lithium, mica, feldspar, silica, and clay. Soils are often a very fine sandy to silty texture, similar to 45c. The region is covered with oak-hickory-pine forest, and Virginia pine is common.

175px-Ecoregions of NC and SC Piedmont 1.JPG Several major land cover transformations have occurred in the Piedmont over the past 200 years, from forest to farm, back to forest, and now in many areas, spreading urban- and suburbanization. The Piedmont contains most of the largest urban areas of the Carolinas, with relatively high regional population densities and rates of growth.


175px-Ecoregions of NC and SC Piedmont 2.JPG Most rocks of the Piedmont are covered by a thick mantle of saprolite, except along some major stream valley bluffs and on a few scattered granitic domes and flatrocks. Rare plants and animals are found on rock outcrops, such as at Forty Acre Rock in Lancaster County, South Carolina. (Photo: Mike Creel, SCDNR)


Ecoregions of NC and SC Piedmont 3.JPG Beaver (Castor canadensis) populations have increased in the Piedmont. They can create wetland habitat for a variety of plant and animal species, reduce downstream sedimentation, and improve water quality.


Ecoregions of NC and SC Piedmont 4.JPG The Carolina wren (Thryothorus ludovicianus), the state bird of South Carolina, nests from the mountains, across the Piedmont and into the Coastal Plain. (Photo:SCDNR)



63. Middle Atlantic Coastal Plain
Ecoregion 63 is found primarily in the Carolinas and other states to the north, and has a broad transitional boundary with Ecoregion 75 to the south. It consists of low elevation, flat plains, with many swamps, marshes, and estuaries. Forest cover in the region, once dominated by longleaf pine in the Carolinas, is now mostly loblolly and some shortleaf pine, with patches of oak, gum, and cypress near major streams, as compared to the mainly longleaf-slash pine forests of the warmer Southern Coastal Plain (75). Its low terraces, marshes, dunes, barrier islands, and beaches are underlain by unconsolidated sediments. Poorly drained soils are common, and the region has a mix of coarse and finer textured soils compared to the mostly coarse soils in the majority of Ecoregion 75. Ecoregion 63 is typically lower, flatter, more poorly drained, and more marshy than Ecoregion 65. Pine plantations for pulpwood and lumber are typical, with some areas of cropland.

63b. The Chesapeake-Pamlico Lowlands and Tidal Marshes occur on the lowest marine terrace with elevations ranging from sea level to about 25 feet. The western boundary of 63b generally occurs at the Suffolk Scarp. The region is characterized by nearly level plains with some broad shallow valleys, seasonally wet soils (Aquults), brackish and fresh streams, and broad estuaries affected by wind tides. It is flatter and lower in elevation than 63e, with a slightly longer growing season than 63e and 65m. Some major areas of cropland are found in the region, growing corn, wheat, soybeans, and potatoes. Lake Mattamuskeet, the largest natural lake in North Carolina, provides valuable wintering areas for geese, swans, ducks, and other birds.

63c. Nonriverine Swamps and Peatlands are flat, poorly drained areas containing organic soils of peat and muck. The dark reddish-brown to black soils, acidic and nutrient-poor, often contain logs, stumps, and other woody matter from bald cypress and Atlantic white cedar trees. Pocosin lakes occur in some areas. The vegetation (Land-cover) of the high and low pocosins contains a dense shrub layer, along with stunted pond pine, swamp red bay, and sweet bay. Swamp forests are dominated by swamp tupelo, bald cypress, and Atlantic white cedar. Fire during drought periods, logging, and construction of drainage ditches have affected natural vegetation patterns. Several areas of mineral and shallow organic soils have been drained and cultivated for crops of corn, soybeans, and wheat.

63d. Virginian Barrier Islands and Coastal Marshes occur in the northeast corner of North Carolina and contain salt (Salt marsh), brackish, and freshwater marshes, dunes, beaches, and barrier islands that enclose Currituck Sound. The Quaternary-age deposits of unconsolidated sand, silt, and clay form dynamic landscapes affected by ocean wave, tide, wind, and river energy. The nearshore ocean water, influenced by the longshore Virginia Current, tends to be colder than in most of 63g, especially south of Cape Hatteras, where warmer Gulf Stream waters occur. On the barrier islands, northern beach grass and deciduous oaks are typical, compared to the sea oats and evergreen live oak more commonly found to the south in 63g. Salt marshes are dominated by saltmarsh and saltmeadow cordgrasses and black needlerush, while the freshwater marshes of upper Currituck Sound contain bulrush, cattail, sawgrass, and big cordgrass. The marshes provide wintering habitat for geese, ducks, and wading birds. Piping plover and loggerhead sea turtles occasionally nest along the beaches.

63e. The Mid-Atlantic Flatwoods occupies the middle portion of the coastal plain in northern North Carolina and southern Virginia. Upland surfaces are wider, lower in elevation, with less local relief, and have more poorly drained soils compared to Ecoregion 65m. Soils such as Aquults and some Udults formed in the mostly Pleistocene-age [[clay]s] and sands. With slow natural subsurface drainage, except near streams, artificial drainage is common for agriculture and forestry operations. Corn, peanuts, and cotton are typical crops. Although similar to 63h, the Mid-Atlantic Flatwoods historically had a lower frequency of fire, less longleaf pine, and a different mix of grasses than in 63h. There are fewer Carolina Bays, and the region tends to be biologically less diverse than 63h in terms of plants and aquatic macroinvertebrates.

63g. The Carolinian Barrier Islands and Coastal Marshes covers most of the North Carolina coast, extending from Bodie Island in the north to North Myrtle Beach, South Carolina in the south. Similar to 63d, the region contains marshes, dunes, beaches, and barrier islands, but it tends to be slightly warmer and wetter. In the north, the boundary with 63d is transitional, and there is a high diversity of vegetation (Land-cover) in the maritime forests in the boundary area where northern and southern maritime forests overlap, such as at Nags Head Woods. The maritime forests include live oak, laurel oak, loblolly pine, red cedar, yaupon holly, wax myrtle, dwarf palmetto, with cabbage palm (Sabal palmetto) in the south. Pamlico Sound is a shallow estuary supporting an important nursery for 90 percent of all the commercial seafood species caught in North Carolina, as well as vast recreational fisheries (Fisheries and aquaculture).

63h. The nearly level coastal plain of the Carolina Flatwoods has less relief, wider upland surfaces, and larger areas of poorly drained soils than the adjacent, higher elevation Ecoregion 65l. Covered by shallow coastal waters during the Pleistocene, the resultant terraces and shoreline-related landforms are covered typically by fine-loamy and coarse-loamy soils, with periodically high water tables. Other areas have clayey, sandy, or organic soils, contributing to the region’s plant diversity. Carolina bays and pocosins are abundant in some areas. The region is a significant center of endemic biota, with more biological diversity and rare species compared to 63e. Pine flatwoods, pine savannas, freshwater marshes, pond pine woodlands, pocosins, and some sandhill communities were once common. Loblolly pine plantations are now widespread with an active forest industry. Artificial drainage for forestry and agriculture is common. North Carolina’s blueberry industry is concentrated on some of the sandy, acidic soils of the region.

63n. The Mid-Atlantic Floodplains and Low Terraces are mostly a continuation of the riverine Ecoregion 65p, although a few floodplains mapped in this region originate within Ecoregion 63. Large, sluggish rivers, deep-water swamps, oxbow lakes, and alluvial deposits with abrupt textural changes characterize 63n. Brownwater floodplains originate in or cross the Piedmont (45) and the sediments contain more weatherable minerals than the blackwater floodplains that have their watersheds entirely within the coastal plain. Cypress-gum swamps are common, along with bottomland hardwoods of wetland oaks, green ash, red maple, and hickories.

175px-Ecoregions of NC and SC Middle Atlantic Coastal Plains 1.JPG Saltmarsh cordgrass (Spartina alterniflora) in the coastal marshes of Ecoregion 63g. The roots of spartina grass help hold the marsh soil and provide a footing for oysters and ribbed mussels. When the grass dies back in the fall, bacteria and fungi break it down into detritus, the base of the marsh food web. The detritus is eaten by crabs, snails, mussels, oysters, clams, and worms, which in turn are food for fish, shellfish, birds, and mammals.


Ecoregions of NC and SC Middle Atlantic Coastal Plains 2.JPG Ghost crabs (Ocypode quadrata) inhabit the dry upper portions of beaches, although several times a day they must return to ocean waters to wet their gills.


Ecoregions of NC and SC Middle Atlantic Coastal Plains 3.JPG Longleaf pine forests are fire-dependent. In the absence of fire, longleaf pine and its associated plants and animals, some of which are rare and occur only in longleaf pine ecosystems, are replaced by other species. (Photo: Ted Borg, SCDNR)


Ecoregions of NC and SC Middle Atlantic Coastal Plains 4.JPG The carnivorous Venus fly traps (Dionaea muscipula) are native to some of the pocosins and peat bogs of Ecoregion 63 in the Carolinas.


Ecoregions of NC and SC Middle Atlantic Coastal Plains 5.JPG The alligator (Alligator mississippiensis) is an integral component of many wetland ecosystems in the southern part of Ecoregion 63. North Carolina is usually considered the northern extent of its habitat range. (Photo: SCDNR)

65. Southeastern Plains
These irregular plains with broad interstream areas have a mosaic of cropland, pasture, woodland, and forest. Natural vegetation (Land-cover) was predominantly longleaf pine, with smaller areas of oak-hickory-pine. On some moist sites, especially in the far south near Florida, Southern mixed forest occurred with beech, sweetgum, southern magnolia, laurel and live oaks, and various pines. The Cretaceous or Tertiary-age sands, silts, and [[clay]s] of the region contrast geologically with the older metamorphic and igneous rocks of the Blue Ridge (66) and Piedmont (45). Elevations and relief are greater than in the Southern Coastal Plain (75), but generally less than in much of the Piedmont. Streams in this area are relatively low-gradient and sandy-bottomed.

65c. The Sand Hills are a rolling to hilly region composed primarily of Cretaceous-age marine sands and clays, capped in places with Tertiary sands, deposited over the crystalline and metamorphic rocks of the Piedmont (45). Many of the droughty, low-nutrient soils formed in thick beds of sand, although some soils contain more loamy and clayey horizons. Some upland areas are underlain by plinthite, and sideslopes tend to have fragipans that perch water and cause lateral flow and seepage. Stream flow is consistent; streams seldom flood or dry up because of the large infiltration capacity of the sandy soil and the great groundwater storage capability of the sand aquifer. On drier sites, turkey oak and blackjack oak grow with longleaf pine and a wiregrass ground cover. Shortleaf-loblolly pine forests and other oak-pine forests are now more widespread due to fire suppression and logging. The Sand Hills are a center of rare plant diversity in the Carolinas. The region is also known for its peach orchards, golf courses, and horse farms.

65l. The Atlantic Southern Loam Plains ecoregion is lower, flatter, more gently rolling, with finer-textured soils than 65c. It is a major agricultural zone, with deep, well-drained soils, and more cropland than 65c or 63h. The flora is varied due to the variety of edaphic conditions, but is generally more mesic than found in 65c, and more xeric than in 63h. The region has the highest concentration of Carolina bays. These are shallow, elliptical depressions, often swampy or wet in the middle with dry sandy rims. Carolina bays not drained for agriculture often contain rare or endangered plant and animal species.

65m. The dissected Rolling Coastal Plain extends south from Virginia and covers much of the northern upper coastal plain of North Carolina. Relief, elevation, and stream gradients are generally greater than in Ecoregion 63 to the east, and soils tend to be better drained. It has a slightly cooler and shorter growing season than 65l, but is a productive agricultural region with typical crops of corn, soybeans, tobacco, cotton, sweet potatoes, peanuts, and wheat. The region appears to be biologically less diverse than the coastal plain regions 65l and 63h to the south.

65p. Southeastern Floodplains and Low Terraces comprise a riverine ecoregion that provides important wildlife corridors and habitat. Composed of alluvium and terrace deposits of sand, clay, and gravel, the region includes large sluggish rivers and backwaters with ponds, swamps, and oxbow lakes. It includes oak-dominated bottomland hardwood forests, and some river swamp forests of bald cypress and water tupelo. Similar to 63n, the flood-prone region includes brownwater floodplains and blackwater floodplains. The brownwater floodplains originate in or cross the Piedmont (45) and the sediments contain more weatherable and mixed minerals than the blackwater floodplains that have their watersheds entirely within the coastal plain. The low terraces are mostly forested, although some cropland or pasture occurs in some areas that are better drained.

175px-Ecoregions of NC and SC Southeastern Plains 1.JPG Longleaf pine forests once covered many portions of the Carolina coastal plain, along with smaller, scattered areas of mixed pine and hardwood forests. Over the past three centuries, naval stores or pine tar production, logging, open range cattle and feral hog grazing, agriculture, and fire suppression removed almost all of the longleaf pine forests.


Ecoregions of NC and SC Southeastern Plains 2.JPG Kudzu is an introduced fast-growing vine that was often planted in the 1930's and 1940's to control soil erosion. The vines can grow a foot per day, climbing and covering trees, poles, and buildings. It can kill trees and other native vegetation by blocking sunlight.

66. Blue Ridge
The Blue Ridge extends from southern Pennsylvania to northern Georgia, varying from narrow ridges to hilly plateaus to more massive mountainous areas with high peaks. The mostly forested slopes, high-gradient, cool, clear streams, and rugged terrain occur primarily on [[metamorphic] rocks] with minor areas of igneous and sedimentary geology. Annual precipitation of over 100 inches can occur in the wettest areas, while dry basins can average as little as 40 inches. The southern Blue Ridge is one of the richest centers of biodiversity in the eastern U.S. It is one of the most floristically diverse ecoregions, and includes Appalachian oak forests, northern hardwoods, and, at the highest elevations in Tennessee and North Carolina, Southeastern spruce-fir forests. Shrub, grass, and heath balds, hemlock, cove hardwoods, and oak-pine communities are also significant.

66c. The New River Plateau is a high, hilly plateau with less relief and a different land cover mosaic than surrounding Blue Ridge ecoregions. It has less dense woodland and forest cover, and more land devoted to pasture, orchards, cropland, livestock and dairy farms, and Christmas tree production. Elevations are generally between 2500-3500 feet, with a few higher peaks. Oak dominates most of the [[forest]s], with beech, birch, hemlock, and poplar on more moist sites and pines on drier areas.

66d. The Southern Crystalline Ridges and Mountains occur primarily on Precambrian-age igneous and high-grade metamorphic rocks, in contrast to the sedimentary and metasedimentary rocks of 66e and 66g. The crystalline rock types are mostly gneiss and schist, covered by well-drained, acidic, loamy soils. Some small areas of mafic and ultramafic rocks also occur, producing more basic soils. The region has greater relief and higher elevations than 66l, 66c, and 66j. Elevations of this rough, dissected region are generally 1200-4500 feet. The southern part of the region is wetter than the north. It is mostly forested, with chestnut oak (and formerly American chestnut) dominating on most slopes and ridges. There are a few small areas of pasture, apple orchards, Fraser fir Christmas tree farms, or minor cropland.

66e. The Southern Sedimentary Ridges in North Carolina consist of small areas near the Tennessee border in western Ashe, Watauga, Mitchell, Yancy, and Madison counties. The disjunct areas contain Cambrian-age sedimentary rocks of shale, sandstone, siltstone, conglomerate, and dolomite. Some metasiltstone or metasandstone occurs, but it is material of very low-grade metamorphism. One of the larger areas, in Madison County, is associated with the Hot Springs Window, an opening where the major thrust sheet was eroded to expose younger, underlying rocks such as the Shady Dolomite and Rome Formation shale and siltstone. Slopes of the region are typically steep and forested, with elevations ranging from 1500-4900 feet.

66g. The Southern Metasedimentary Mountains in North Carolina contain rocks that are not as strongly metamorphosed as the gneisses and schists of 66d. The geologic materials are mostly late Pre-Cambrian and include metagraywacke, metasiltstone, metasandstone, metaconglomerate, slate, schist, phyllite, and quartzite. These are steep, dissected, biologically diverse mountains that are densely forested. The Appalachian oak forests and, at higher elevations, the northern hardwoods forests include a variety of oaks and pines, as well as silverbell, hemlock, yellow poplar, basswood, buckeye, yellow birch, and beech. Much of the region is public land managed by the National Park Service or U.S. Forest Service.

66i. The High Mountains ecoregion includes several disjunct high-elevation areas generally above 4500 feet. The region has a more severe, boreal-like climate than surrounding regions, with wind and ice affecting vegetation (Land-cover), and it has frigid soils rather than [[mesic soi. Evergreen red spruce and Fraser fir forests are found at the higher elevations, and red oak forests and northern hardwood forests with beech, yellow birch, yellow buckeye, and sugar maple are common. The spruce-fir forests have been affected by the balsam wooly adelgid, a non-native insect that kills mature Fraser firs, and some forest growth declines are possibly linked to air pollutants. Heath balds dominated by evergreen rhododendron and mountain laurel, and grassy balds are found on some slopes and ridgetops. Northern flying squirrels, Blackburnian warblers, black-capped chickadees, and common ravens are seen in this region.

66j. The Broad Basins ecoregion is drier, has lower elevations and less relief than the more mountainous Blue Ridge regions (66g, 66d). It also has less bouldery colluvium than those two surrounding regions and more saprolite. The soils are mostly deep, well-drained, loamy to clayey Ultisols, although there are variations between the uplands, the high and low terraces, and the floodplains. The Asheville basin has the lowest annual precipitation amounts in North Carolina, receiving less than 42 inches. Compared to the higher mountainous ecoregions of 66, the Broad Basins have a mix of oaks and pines more similar to the Piedmont (45), with more shortleaf and Virginia pine, and white, southern red, black, and scarlet oaks. Although some areas of this rolling foothills region are mostly forested, overall it has more pasture, cropland, industrial [[land use]s], and human settlement than other Blue Ridge ecoregions. Outlines of abandoned fields with pine-hardwood succession are apparent on many lower slopes.

66k. Similar to some parts of 66d, the Amphibolite Mountains are a botanically diverse area with many rare species, including some relict and disjunct species from areas much further north. The rugged, steeply sloping mountains are composed of Precambrian amphibolite and gneiss. The amphibolite, a metamorphosed black volcanic rock, formed from lavas that spilled on the floor of a shallow sea, mixing with layers of mud, sand, and volcanic ash. In some areas this rock weathers to produce shallow soils high in calcium and Magnesium, and less acidic than most Appalachian soils. Oak forests (formerly American chestnut forests) dominate on south, east, and west facing slopes with an understory of Catawba rhododendron, mountain laurel, flame azalea, and dogwood. Cove forests and northern hardwood forests are found on north slopes, and include sugar maple, ash, yellow birch, tulip tree, and basswood.

66l. The open low mountains of the Eastern Blue Ridge Foothills are lower in elevation (1000-2800 feet) than most Blue Ridge regions and have more Piedmont influences. The region includes the Brushy Mountains to the north and the South Mountains to the south. Covered with mixed oak and oak-hickory-pine forests, these mountains tend to be slightly drier and warmer than most of Ecoregion 66. The South Mountains contain forested areas that harbor many uncommon or rare plant species, including turkey beard (Xerophyllum asphodeloides) on xeric ridges and one of North America’s rarest orchids, the small whorled pogonia (Isotria medeoloides).

66m. The prominent ridges and knobs of the Sauratown Mountains rise more than 1000 feet above the rolling Piedmont (45) surface. Sometimes called monadnocks or inselbergs, these isolated mountain outliers are formed in part by their caps of erosion-resistant quartzite. The region has both Piedmont and Blue Ridge vegetation (Land-cover) communities: mostly oak and oak-pine forests with some Canadian and Carolina hemlock in moist areas. Other mountain flora found here include rhododendron, azalea, galax, mountain laurel, pitch pine, table mountain pine, and various ferns.

175px-Ecoregions of NC and SC Blue Ridge 1.JPG The Blue Ridge is part of one of the richest temperate broadleaf forests in the world, with a high diversity of flora and fauna. Black bear, deer, wild boar, turkey, grouse, songbirds, reptiles, many species of amphibians, thousands of species of invertebrates, and a variety of small mammals are found here. (Photo: SCDNR)


Ecoregions of NC and SC Blue Ridge 2.JPG The saw-whet owl (Aegolius acadicus), a species of special concern in North Carolina, often roosts during the day in red spruce trees of 66i and nests in cavity trees such as yellow birch or in nest boxes set out for flying squirrels. (Photo: John and Karen Hollingsworth)


Ecoregions of NC and SC Blue Ridge 3.JPG The high-elevation spruce-fir forests of 66i are buffeted by higher winds, colder temperatures, and greater precipitation than lower elevations. Growth declines, insect damage, and air pollution are continuing concerns.


Ecoregions of NC and SC Blue Ridge 4.JPG Black bears are found in many parts of the Blue Ridge, but tend to be reclusive by nature. (Photo: John Lucas, SCDNR)


Ecoregions of NC and SC Blue Ridge 5.JPG Catawba rhododendron grow at various elevations in the Blue Ridge, often densely on balds at higher elevations. (Photo: Joe and Monica Cook)


Ecoregions of NC and SC Blue Ridge 6.JPG The red squirrel (Tamiasciurus hudsonicus) is one of the smaller but louder squirrels of the Blue Ridge. It collects nuts, seeds, birds' eggs, and mushrooms from forests generally higher in elevation than occupied by the gray squirrel.

75. Southern Coastal Plain
The Southern Coastal Plain extends from South Carolina and Georgia, through much of central Florida, and along the Gulf coast lowlands of the Florida Panhandle, Alabama, and Mississippi. From a national perspective, it appears to be mostly flat plains, but it is a heterogeneous region also containing barrier islands, coastal lagoons, marshes, and swampy lowlands along the Gulf and Atlantic coasts. In Florida, an area of discontinuous highlands contains numerous lakes. This ecoregion is generally lower in elevation with less relief and wetter soils than Ecoregion 65. It is warmer and has a different mix of vegetation than Ecoregion 63. Once [[cover]ed] by a variety of forest communities that included trees of longleaf pine, slash pine, pond pine, beech, sweetgum, southern magnolia, white oak, and laurel oak, land cover in the ecoregion as a whole is now mostly slash and loblolly pine with oak-gum-cypress forest in some low lying areas, citrus groves in Florida, pasture for beef cattle, and urban.

75i. Floodplains and Low Terraces are a continuation of the riverine 65p ecoregion across the Southern Coastal Plain. Similar to 63n, the broad floodplains and terraces of major rivers, such as the Savannah in South Carolina, comprise the region. Composed of stream alluvium and terrace deposits of sand, silt, clay, and gravel, along with some organic muck and swamp deposits, the region includes large sluggish rivers and backwaters with ponds, swamps, and oxbow lakes. River swamp forests of bald cypress and water tupelo and oak-dominated bottomland hardwood forests provide important wildlife habitat.

75j. The Sea Islands/Coastal Marsh region contains the lowest elevations in South Carolina and is a highly dynamic environment affected by ocean wave, wind, and river action. Mostly sandy soils are found on the barrier islands, while organic and clayey soils often occur in the freshwater, brackish, and [[salt (Salt marsh)] marshes]. Maritime forests of live oak, red cedar, slash pine, and cabbage palmetto grow on parts of the sea islands, and various species of cordgrass, saltgrass, and rushes are dominant in the marshes. The coastal marshes are important nursery areas for fish, crabs, shrimp, and other marine species. During the colonial and antebellum periods in the 1700's and 1800's, a plantation agriculture economy dominated the region, producing rice, indigo, and Sea Island cotton.

175px-Ecoregions of NC and SC Southern Coastal Plain 1.JPG Tolerant of salt spray, dry sandy soils, or saturated conditions, cabbage palms (Sabal palmetto) are uniquely adapted to the coastal environment. Flexible trunks and shredded, divided leaves bend but tend not to break in hurricanes. (Photo: Allen Sharpe, SCETV)

Notes

  • The full, original version of this entry is located here: http://www.epa.gov/wed/pages/ecoregions/ncsc_eco.htm. That description contains additional maps, as well as information on the physiography, geology, soil, potential natural vegetation, and the land use and land cover of the ecoregion.
  • PRINCIPAL AUTHORS: Glenn E. Griffith (NRCS), James M. Omernik (USEPA), Jeffrey A. Comstock (Indus Corporation), Michael P. Schafale (NCDENR), W. Henry McNab (USFS), David R. Lenat (NCDENR), Trish F. MacPherson (NCDENR), James B. Glover (SCDHEC), and Victor B. Shelburne (Clemson University).
  • COLLABORATORS AND CONTRIBUTORS: James E. Harrison (USEPA), David L. Penrose (NCDENR), Ronald C. Ahle (South Carolina Department of Natural Resources [SCDNR]), Roy L.Vick, Jr. (NRCS), Ben Stuckey, Jr. (NRCS), Dennis L. Law (USFS), Robert K. Peet (University of North Carolina), Richard T. Renfrow (SCDHEC), Paul G. Nystrom (SCDNR), Richard L. Scharf (SCDNR), Chip Smith (NRCS), Alan J. Woods (Dynamac Corporation), and Thomas R. Loveland (USGS).
  • REVIEWERS: Stanley W. Buol (North Carolina State University), Berman D. Hudson (NRCS), Charles F. Kovacik (University of South Carolina), Rudy E. Mancke (University of South Carolina), and Gerard McMahon (USGS).
  • CITING THIS POSTER: Griffith, G.E., Omernik, J.M., Comstock, J.A., Schafale, M.P., McNab, W.H., Lenat, D.R., MacPherson, T.F., Glover, J.B., and Shelburne, V.B., 2002, Ecoregions of North Carolina and South Carolina, (color poster with map, descriptive text, summary tables, and photographs): Reston, Virginia, U.S. Geological Survey (map scale 1:1,500,000).
  • This project was partially supported by funds from the North Carolina Department of Environment and Natural Resources and the South Carolina Department of Health and Environmental Control through grants provided by the U.S. Environmental Protection Agency Region IV under the provisions of Sections 104(b) and 319(h) of the Federal Water Pollution Control Act.

Literature Cited

  • Bailey, R.G., Avers, P.E., King, T., and McNab, W.H., eds., 1994, Ecoregions and subregions of the United States (map) (supplementary table of map unit descriptions compiled and edited by McNab, W.H. and Bailey, R.G.): Washington, D.C., U.S. Department of Agriculture-Forest Service, scale 1:7,500,000.
  • Bryce, S.A., Omernik, J.M., and Larsen, D.P., 1999, Ecoregions - a geographic framework to guide risk characterization and ecosystem management: Environmental Practice, v. 1, no. 3, p. 141-155.
  • Commission for Environmental Cooperation Working Group, 1997, Ecological regions of North America - toward a common perspective: Montreal, Quebec, Commission for Environmental Cooperation, 71 p.
  • Gallant, A.L., Whittier, T.R., Larsen, D.P., Omernik, J.M., and Hughes, R.M., 1989, Regionalization as a tool for managing environmental resources: Corvallis, Oregon, U.S. Environmental Protection Agency, EPA/600/3-89/060, 152 p.
  • McMahon, G., Gregonis, S.M., Waltman, S.W., Omernik, J.M., Thorson, T.D., Freeouf, J.A., Rorick, A.H., and Keys, J.E., 2001, Developing a spatial framework of common ecological regions for the conterminous United States: Environmental Management, v. 28, no. 3, p. 293-316.
  • Omernik, J.M., 1987, Ecoregions of the conterminous United States (map supplement): Annals of the Association of American Geographers, v. 77, no. 1, p. 118-125, scale 1:7,500,000.
  • Omernik, J.M., 1995, Ecoregions - a spatial framework for environmental management, in Davis, W.S., and Simon, T.P., eds., Biological assessment and criteria-tools for water resource planning and decision making: Boca Raton, Florida, Lewis Publishers, p. 49-62. ISBN: 0873718941.
  • Omernik, J.M., Chapman, S.S., Lillie, R.A., and Dumke, R.T., 2000, Ecoregions of Wisconsin: Transactions of the Wisconsin Academy of Sciences, Arts and Letters, v. 88, no. 2000, p. 77-103.
  • U.S. Department of Agriculture-Soil Conservation Service, 1981, Land resource regions and major land resource areas of the United States: Agriculture Handbook 296, 156 p.
  • U.S. Environmental Protection Agency, 2002, Level III ecoregions of the continental United States (revision of Omernik, 1987): Corvallis, Oregon, U.S. Environmental Protection Agency-National Health and Environmental Effects Research Laboratory, Map M-1, various scales.
  • Wiken, E., 1986, Terrestrial ecozones of Canada: Ottawa, Environment Canada, Ecological Land Classification Series no. 19, 26 p. ISBN: 0662147618.




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Citation

Omernik, J., & Griffith, G. (2008). Ecoregions of North Carolina and South Carolina (EPA). Retrieved from http://editors.eol.org/eoearth/wiki/Ecoregions_of_North_Carolina